Over the past 5 years, the Center for Children's Environmental Health Research at the University of California, Berkeley has successfully created a fully coordinated research program that addresses the unique environmental health needs of primarily Latino farmworker children living in an agricultural community. The investigators have focused their research on pesticide exposures, their potential health consequences, and community-based exposure prevention strategies. A strong community partnership and infrastructure has been developed with extensive outreach to constituent groups, service providers, and policy makers, and the investigators have received awards from both the University and the community. In addition, the investigators have leveraged Center resources to obtain additional funding for numerous other community and scientific projects. The core of the Center has been the CHAMACOS (Center for the Health Assessment of Mothers and Children of Salinas) project, conducted in collaboration with a coalition of community health care providers and agencies. CHAMACOS, which means 'small child' in Mexican Spanish, is a longitudinal birth cohort study of pregnant women and children living in the agricultural community of the Salinas Valley, Monterey County, California. The CHAMACOS cohort includes primarily low-income Mexican immigrant farmworkers and their families, and thus, provides a unique opportunity to examine prospectively the influence of prenatal and early childhood exposures encountered in an agricultural environment, such as to pesticides and bioaerosols, on the health of children. Over the next 5 year, the investigators propose to follow the CHAMACOS cohort into the school years and to determine whether prenatal and childhood exposure have impacted their neurodevelopment, respiratory health, and somatic growth. Moreover, they propose to expand the scope of the Center in three related and complementary directions: first, laboratory investigations will be conducted to understand the mechanisms of immuno- and neuro-toxicity of pesticides; second, exposure-related studies will be conducted to better understand the routes and pathways of pesticide exposure to children; and third, outreach will be extended to constituent groups within the immediate Salinas community and to similar populations in Monterey County, the state of California, and throughout the nation. These activities are aimed at accomplishing the Center's ultimate goal: to translate research findings into sustainable strategies to reduce pesticide and other environmental exposures to children, and thus reduce the incidence of environmentally related childhood disease.